#!/bin/bash

echo "Creating lenny node..."

configure_ubuntu()
{
    rootfs=$1
    hostname=$2

	# disable selinux in ubuntu
    mkdir -p $rootfs/selinux
    echo 0 > $rootfs/selinux/enforce

	# add host root ssh access
    mkdir $rootfs/root/.ssh
    chmod 0600 $rootfs/root/.ssh
	cat <<-EOF > $rootfs/root/.ssh/authorized_keys
ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQDCguB7XL3ARzLZYLsIMZe4UUO371m+H5C6V8MhtmSlgXtgHDo7eZhNSm5zCeoyGd32OKeLxuxCCEkXfDDF1aa2a6twcASE3pmWNdnBS7auiOH4P7g+eQ4Aw9v7DdESbIVgHF/NDiAEFFdmApYNM3oCX2FhEVNVKxkkIokUr4axYFJzmJ6Xoi5Sd8JtPC85FZVXqDucZDnHQlOcCkbSo0UOmsWQGwtu8eUHoDeUG0dB8ntb9xlBeLctdrAPhuFYCX8IfFkdcakkzv61ETPbKE6g9wdTDC/TEep7/AHGYmarziRnwKiVOL1jnE1coOJLqy8wOC3dKGmRZy9D4sTc+FRV root insecure public key
	EOF

	cp /usr/lib/lxc/templates/files/rc.local $rootfs/etc/rc.local

    # set the hostname
    cat <<EOF > $rootfs/etc/hostname
$hostname
EOF
    # set minimal hosts
    cat <<EOF > $rootfs/etc/hosts
127.0.0.1 localhost $hostname
EOF

    cat <<EOF > $rootfs/etc/inittab
id:3:initdefault:
si::sysinit:/etc/init.d/rcS
l0:0:wait:/etc/init.d/rc 0
l1:1:wait:/etc/init.d/rc 1
l2:2:wait:/etc/init.d/rc 2
l3:3:wait:/etc/init.d/rc 3
l4:4:wait:/etc/init.d/rc 4
l5:5:wait:/etc/init.d/rc 5
l6:6:wait:/etc/init.d/rc 6
# Normally not reached, but fallthrough in case of emergency.
z6:6:respawn:/sbin/sulogin
1:2345:respawn:/sbin/getty 38400 console
c1:12345:respawn:/sbin/getty 38400 tty1 linux
c2:12345:respawn:/sbin/getty 38400 tty2 linux
c3:12345:respawn:/sbin/getty 38400 tty3 linux
c4:12345:respawn:/sbin/getty 38400 tty4 linux
EOF

    # reconfigure some services
    if [ -z "$LANG" ]; then
		chroot $rootfs locale-gen en_US.UTF-8
		chroot $rootfs update-locale LANG=en_US.UTF-8
    else
		chroot $rootfs locale-gen $LANG
		chroot $rootfs update-locale LANG=$LANG
    fi

    echo "Set root password to 'root'"
    echo "root:root" | chroot $rootfs chpasswd

    return 0
}

copy_ubuntu()
{
    cache=$1
    arch=$2
    rootfs=$3

    # make a local copy of the miniubuntu
    echo "Extracting rootfs image to $rootfs ..."
    mkdir $rootfs
    tar zxf $cache/lenny-$arch.tar.gz -C $rootfs || return 1
    return 0
}

install_ubuntu()
{
    cache="/var/cache/lxc"
    rootfs=$1
    mkdir -p /var/lock/subsys/
    (
	flock -n -x 200
	if [ $? -ne 0 ]; then
	    echo "Cache repository is busy."
	    return 1
	fi

	arch=$(arch)
	if [ "$arch" == "x86_64" ]; then
	    arch=amd64
	fi

	if [ "$arch" == "i686" ]; then
	    arch=i386
	fi

	echo "Checking image cache in $cache/rootfs-$arch ... "
	if [ ! -e "$cache/rootfs-$arch" ]; then
	    if [ $? -ne 0 ]; then
		echo "Failed to download 'ubuntu base'"
		return 1
	    fi
	fi

	copy_ubuntu $cache $arch $rootfs
	if [ $? -ne 0 ]; then
	    echo "Failed to copy rootfs"
	    return 1
	fi

	return 0

	) 200>/var/lock/subsys/lxc

    return $?
}

copy_configuration()
{
    path=$1
    rootfs=$2
    name=$3

    cat <<EOF >> $path/config
lxc.utsname = $name

lxc.tty = 4
lxc.pts = 1024
lxc.rootfs = $rootfs
lxc.mount  = $path/fstab

lxc.cgroup.devices.deny = a
# /dev/null and zero
lxc.cgroup.devices.allow = c 1:3 rwm
lxc.cgroup.devices.allow = c 1:5 rwm
# consoles
lxc.cgroup.devices.allow = c 5:1 rwm
lxc.cgroup.devices.allow = c 5:0 rwm
lxc.cgroup.devices.allow = c 4:0 rwm
lxc.cgroup.devices.allow = c 4:1 rwm
# /dev/{,u}random
lxc.cgroup.devices.allow = c 1:9 rwm
lxc.cgroup.devices.allow = c 1:8 rwm
lxc.cgroup.devices.allow = c 136:* rwm
lxc.cgroup.devices.allow = c 5:2 rwm
# rtc
lxc.cgroup.devices.allow = c 254:0 rwm
EOF

    cat <<EOF > $path/fstab
proc            $rootfs/proc         proc    nodev,noexec,nosuid 0 0
devpts          $rootfs/dev/pts      devpts defaults 0 0
sysfs           $rootfs/sys          sysfs defaults  0 0
EOF

    if [ $? -ne 0 ]; then
	echo "Failed to add configuration"
	return 1
    fi

    return 0
}

clean()
{
    cache="/var/cache/lxc"

    if [ ! -e $cache ]; then
	exit 0
    fi

    # lock, so we won't purge while someone is creating a repository
    (
	flock -n -x 200
	if [ $? != 0 ]; then
	    echo "Cache repository is busy."
	    exit 1
	fi

	echo -n "Purging the download cache..."
	rm --preserve-root --one-file-system -rf $cache && echo "Done." || exit 1
	exit 0

    ) 200>/var/lock/subsys/lxc
}

usage()
{
    cat <<EOF
$1 -h|--help -p|--path=<path> --clean
EOF
    return 0
}

options=$(getopt -o hp:n:c -l help,path:,name:,clean -- "$@")
if [ $? -ne 0 ]; then
    usage $(basename $0)
    exit 1
fi
eval set -- "$options"

while true
do
    case "$1" in
	-h|--help)      usage $0 && exit 0;;
	-p|--path)      path=$2; shift 2;;
	-n|--name)      name=$2; shift 2;;
	-c|--clean)     clean=$2; shift 2;;
	--)             shift 1; break ;;
        *)              break ;;
    esac
done

if [ ! -z "$clean" -a -z "$path" ]; then
    clean || exit 1
    exit 0
fi

if [ -z "$path" ]; then
    echo "'path' parameter is required"
    exit 1
fi

if [ "$(id -u)" != "0" ]; then
    echo "This script should be run as 'root'"
    exit 1
fi

rootfs=$path/rootfs

install_ubuntu $rootfs
if [ $? -ne 0 ]; then
    echo "failed to install ubuntu"
    exit 1
fi

configure_ubuntu $rootfs $name
if [ $? -ne 0 ]; then
    echo "failed to configure ubuntu for a container"
    exit 1
fi

copy_configuration $path $rootfs $name
if [ $? -ne 0 ]; then
    echo "failed write configuration file"
    exit 1
fi

if [ ! -z $clean ]; then
    clean || exit 1
    exit 0
fi
